update Code

libraries/FlowMeter-master/examples/Calibration/Calibration.ino

@@ -0,0 +1,48 @@
+#include <FlowMeter.h>  // https://github.com/sekdiy/FlowMeter
+
+// enter your own sensor properties here, including calibration points
+FlowSensorProperties MySensor = {60.0f, 5.5f, {1, 1, 1, 1, 1, 1, 1, 1, 1, 1}};
+FlowMeter Meter = FlowMeter(2, MySensor);
+
+// timekeeping variables
+long period = 1000;   // one second (in milliseconds)
+long lastTime = 0;
+
+// define an 'interrupt service routine' (ISR)
+void MeterISR() {
+    // let our flow meter count the pulses
+    Meter.count();
+}
+
+void setup() {
+    // prepare serial communication
+    Serial.begin(9600);
+
+    // enable a call to the 'interrupt service handler' (ISR) on every rising edge at the interrupt pin
+    attachInterrupt(INT0, MeterISR, RISING);
+
+    // sometimes initializing the gear generates some pulses that we should ignore
+    Meter.reset();
+}
+
+void loop() {
+    // do some timekeeping
+    long currentTime = millis();
+    long duration = currentTime - lastTime;
+
+    // wait between display updates
+    if (duration >= period) {
+
+        // process the counted ticks
+        Meter.tick(duration);
+
+        // output some measurement result
+        Serial.println("FlowMeter - current flow rate: " + String(Meter.getCurrentFlowrate()) + " l/min, " +
+                       "nominal volume: " + String(Meter.getTotalVolume()) + " l, " +
+                       "compensated error: " + String(Meter.getCurrentError()) + " %, " +
+                       "duration: " + String(Meter.getTotalDuration() / 1000) + " s.");
+
+        // prepare for next cycle
+        lastTime = currentTime;
+    }
+}